The emergence of an increasingly competitive and managed health care marketplace has placed an unprecedented premium on increasing the value of medical services. In this environment, the traditional American model for hospital care, in which primary care providers (PCPs) manage their own patients in the hospital, is quickly being replaced by a new model in which hospital care is provided by hospital-based physicians, a group we have called "hospitalists". The hospitalist model has a number of potential advantages over the traditional PCP-based model for hospital care: hospitalists can become expert in both clinical and logistical aspects of increasingly complex hospital care, they can be available to patients, families, and consultants throughout the day, they can participate in inpatient practice guideline and quality improvement activities, and they can be held accountable for the cost and quality of inpatient care. Moreover, their presence frees primary care physicians to be more available to their patients in the office setting. However, the hospitalist movement raises a number of concerns as well: how to maintain communication between the inpatient and outpatient settings, how to promote satisfaction among hospitalized patients, and how to ensure that primary care physicians remain content in their roles and do not lose vital clinical skills. Despite the rapid adoption of hospitalist systems throughout the country, there is little data available concerning the costs, outcomes, and patient and provider satisfaction achieved by this new model. There has also been little systematic consideration of the many policy issues that flow from the emergence of this new speciality, including its impact on medical manpower, organized medicine, medical education, and credentialing. We propose a national conference, to be held on December 5-6, 1997 in San Francisco, to address each of these issues. Speakers will be leaders from managed care organizations, medical groups, employer cooperatives, organized internal medicine, credentialing organizations, and academic medical centers. In addition, a number of practicing hospitalists from all over America will describe how each of their own systems developed and functions. We believe this conference will play a vital role in setting a research and policy agenda for this rapidly emerging new movement in American medicine.